June 20, 2017

Living in families is a good idea

  • All the benefits of grouping (Krause and Ruxton 2002)

  • Costs shared with relatives (Hamilton 1964)

  • Higher rank in groups (Poisbleau et al. 2006, Scheiber et al. 2013)

Goose families are variable

  • Multi-year bonds (Warren et al. 1993)

  • Larger spp. stay together longer (Johnson and Raveling 1988, Warren et al. 1993, Jónsson and Afton 2008)

  • Populations may segregate in winter (Vangilder and Smith 1985)

We want to know

  • Wintering site ~ family size

  • Family size ~ time ↓

  • Family size ~ flock size ↓

  • \(p(split)\) ~ flight activity ↑

Eurasian whitefronts

Hypothesis 1

Hamilton, W. 1964. The genetical evolution of social behaviour. i. - Journal of Theoretical Biology 7: 1–16.

Johnson, J. C. and Raveling, D. G. 1988. Weak family associations in cackling geese during winter: Effects of body size and food resources on goose social organization. - Waterfowl in winter: 71–89.

Jónsson, J. E. and Afton, A. D. 2008. Lesser Snow geese and Ross’s geese form mixed flocks during winter but differ in family maintenance and social status. - The Wilson Journal of Ornithology 120: 725–731.

Krause, J. and Ruxton, G. D. 2002. Living in groups. - Oxford University Press.

Poisbleau, M. et al. 2006. Social dominance correlates and family status in wintering dark-bellied brent geese, Branta bernicla bernicla. - Animal Behaviour 71: 1351–1358.

Scheiber, I. B. et al. 2013. The social life of greylag geese. - Cambridge University Press.

Vangilder, L. D. and Smith, L. M. 1985. Differential distribution of wintering brant by necklace type. - The Auk 102: 645–647.

Warren, S. M. et al. 1993. Extended parent-offspring relationships in Greenland White-fronted geese (Anser albifrons flavirostris). - The Auk 110: 145–148.